Help me diagnose dead alt?
Senior Member
Joined: Dec 2010
Posts: 882
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From: Michigan (Home state) Stationed in Montana
Year: 1993
Model: Grand Cherokee
Engine: 5.2L MPI V8 (318)
Remember, if you submerge that splash plate, anything that goes above it will stay up there. You'd be better off fabbing a somewhat encased metal shell for the alt itself. But with that also, if it wasn't fully encased, it would let things in. And they'd stay there up against it.
Thread Starter
Seasoned Member
Joined: Dec 2011
Posts: 319
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From: Wenatchee, WA
Year: 1990
Model: Cherokee
Engine: 4.0L Renix
Remember, if you submerge that splash plate, anything that goes above it will stay up there. You'd be better off fabbing a somewhat encased metal shell for the alt itself. But with that also, if it wasn't fully encased, it would let things in. And they'd stay there up against it.
Senior Member
Joined: Jan 2011
Posts: 645
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From: Dalton, MA
Year: 1998
Model: Cherokee
Engine: 4.0 H.O. 180K miles
I killed my alternator with mud after going through a 3+ foot deep puddle, had to replaced it. The thing seized right up after sitting a day and screeched the hell out of the belt. Sprayed it with a hose and worked it a bit to free it up but it was no longer creating current.
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Joined: Feb 2009
Posts: 717
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From: Highlands Ranch Co.
Year: 1985 shell
Model: Cherokee
Engine: 1996 6 cylinder Briggs & Stratton
Thread Starter
Seasoned Member
Joined: Dec 2011
Posts: 319
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From: Wenatchee, WA
Year: 1990
Model: Cherokee
Engine: 4.0L Renix
Really? Never even considered getting it rebuilt. Hmm. Can they increase the output a little too? What is the stock 1990 alt output anyone know? Mines the normal 4.0L not HO.
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Seasoned Member
Joined: Dec 2011
Posts: 319
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From: Wenatchee, WA
Year: 1990
Model: Cherokee
Engine: 4.0L Renix
Some great reading for everybody.
http://www.pirate4x4.com/tech/billavista/Wiring/Part2/
http://www.pirate4x4.com/tech/billavista/Wiring/Part2/
Thread Starter
Seasoned Member
Joined: Dec 2011
Posts: 319
Likes: 0
From: Wenatchee, WA
Year: 1990
Model: Cherokee
Engine: 4.0L Renix
Some great reading for everybody.
http://www.pirate4x4.com/tech/billavista/Wiring/Part2/
http://www.pirate4x4.com/tech/billavista/Wiring/Part2/
Seasoned Member
Joined: Jul 2009
Posts: 398
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From: Bremerton
Year: 87
Model: Cherokee
Engine: 4.0
I go through mud all the time and it has never affected my alt. A simple test for checking a bad alt is check the voltage at the battery with the jeep running. If it goes down its not charging if it sits around 14-14.5 its good.
CF Veteran
Joined: Oct 2011
Posts: 1,339
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From: Yakima
Year: 1990
Model: Cherokee
Engine: 4.0 I6
Thread Starter
Seasoned Member
Joined: Dec 2011
Posts: 319
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From: Wenatchee, WA
Year: 1990
Model: Cherokee
Engine: 4.0L Renix
Yeaaa my voltage has been around like low 11's the past few weeks before my alt "died"..
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Joined: Aug 2011
Posts: 43,971
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From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0



